Posted
by
timothy
on Monday January 28, 2013 @04:30AM
from the let's-terraform-earth dept.

Living in dense cities makes for certain efficiencies: being able to walk or take mass transit to work, living in buildings with (at least potentially) efficient HVAC systems, and more. That's why cities have been lauded in recent years for their (relatively) low environmental impact. But it seems at least one aspect of city life has an environmental effect felt at extreme distances from the cities themselves: waste heat. All those tightly packed sources of heat, from cars to banks of AC units, result in temperature changes not just directly (and locally) but by affecting weather systems surrounding the source city.
From the article:
"The released heat is changing temperatures in areas more than 1,000 miles away (1609 kilometers). It is warming parts of North America by about 1 degree Fahrenheit (0.6 degrees Celsius) and northern Asia by as much as 1.8 degrees Fahrenheit (1 degree Celsius), while cooling areas of Europe by a similar amount, scientists report in the journal Nature Climate Change.
The released heat (dubbed waste heat), it seems, is changing atmospheric circulation, including jet streams — powerful narrow currents of wind that blow from west to east and north to south in the upper atmosphere.
This impact on regional temperatures may explain a climate puzzle of sorts: why some areas are having warmer winters than predicted by climate models, the researchers said. In turn, the results suggest this phenomenon should be accounted for in models forecasting global warming."

Seriously, if you have one rough rounded number you can't do an exact convert and add false precision to the statement...

At least they didn't quibble about the difference between the UK Statute mile and the US Survey mile (the US mile is longer by 3.2mm [unc.edu]), or even the rounding error of over a third of a km in their conversion.

I took chemistry a long time ago. The teacher said if you turn in dissociation constants with more than two decimal places, he'd mark them wrong (for those students who did their calculations on digital devices and copied all 10 digits of result.) He explained that these were chaotic events and everything past the second digit was noise.

I think the point of the very specific number above is simply it being a single data point. In fact heat effects may travel tremendously further than even that. More important, if heat is shifting the jet stream, secondary and tertiary effects may be happening downstream many thousands of miles and include drought, flood, or unseasonable weather. As well, the city heat drives low altitude moisture and chemical particulates (soot and industrial dust) into the higher atmosphere (potentially punching a hole in the common inversion layers) and that moisture/nucleation may have significant down wind impacts as well. I'm looking forward to seeing what the models say. If we're lucky, the effect will be more cloud cover, increasing earth's albido, and be a thermal cooling factor over-all. If not, it may be adding to a climate that is growing ever more unstable and that's bad news for everyone.

My question is, why isn't anyone talking about the air pollution problems happening this month in China? Air that's being called lethal by some, over 40x more polluted that world health limits recommend. Here's a story [freerepublic.com] about a factory that burned for 3 hours because nobody could tell the difference between the smoke and the pall of smog. My greatest concern is that over the last ten years there have been several events of smog from China reaching the western U.S., this being the worst smog event in remembrance, there is a real chance it could make it to America. Thankfully, it winter and most likely will be washed into the sea by storm systems. Had this been summer we would certainly be facing serious environmental threat. So why isn't this a HUGE conversation right now, virtually nobody is even talking about it.

Augh! Talk about teaching a good idea for the wrong reasons. If you can measure your original data to n significant figures, and your conversion factors and constants and so on go to the same number of significant figures, then there's no reason why you can't quote the final value with the same precision. (I'm glossing things over here; addition and subtraction work differently to multiplication and division.)

There's nothing magical about "two decimal places", especially given that the number of decimal pla

Since the dissociation constant is a ratio of dissociated ion vs associated whole dissolved molecules in solution (at equilibrium between between ionization and recombining) the value is completely independent of quantities or units of measure (the ratio between the two at let's say STP would remain constant, ergo Dissociation Constant.). Also because this process is incredibly sensitive to temperature and mechanical motion (including brownian motion), fine scale measurements are very noisy in nature. Which

Actually strictly speaking your dissociation constants have units that depend upon the reaction, given that they're a special case of the equilibrium constant. (It seems it's typical to eliminate units by some means or another.) While I understand that the measurements are tricky and noisy (I was never much good at labs) there is no intrinsic physical limit on their precision, and it would be more informative to point out that you can have no greater precision in your final results than you have in your inp

Hey, You, a student of Dr Swaminathan too? He too would give a D for any lab sheet turned in without calculating the estimate of experimental error, or if the reported result had too many significant digits. But he was doing freshman Physics at IIT-M, not chemistry.

It's a bit rich to go on about "the other top nations" refusing to join in when the US flatly refuses to join the climate change accords that the rest of the developed (and much of the developing) world have established.

It's a bit rich to go on about "the other top nations" refusing to join in when the US flatly refuses to join the climate change accords that the rest of the developed (and much of the developing) world have established.

So what? Those accords haven't done jack shit in the past, they are largely a symbolic gesture and none of the nations who did agree to the last ones managed to live up to what they promised. You seem to think that not sitting down at a table in a room full of people is the same thing as doing nothing, which is about as far from the truth as is possible. There is a large and active environmental movement in the US, and we are actively taking steps to reduce emissions. Just because we're not willing to give

A tour guide in front of the pyramid of Gizah : This pyramid is 4507.5 years old.A tourist : Wow! Which dating methodology did you use to achieve such a precision?Tour guide : It's quite simple actually. I got this job in summer 2005, and it was 4500 years old at that time.

It says "more than", and it is obvious from context that it doesn't exclude an effect for less than 1000 miles (actually, the absolute biggest effect of a city is at 0 miles distance for sure). Therefore it cannot be an exact number.

Also, how probable is it that a natural phenomenon agrees to four significant digits with a completely arbitrary length unit not based on that phenomenon?

It says "more than", and it is obvious from context that it doesn't exclude an effect for less than 1000 miles (actually, the absolute biggest effect of a city is at 0 miles distance for sure). Therefore it cannot be an exact number.

Also, how probable is it that a natural phenomenon agrees to four significant digits with a completely arbitrary length unit not based on that phenomenon?

If you ever work with large sets of data, you'd be amazed at how many events occur precisely at midnight, down to the nanosecond./sarcasm

... But this directly contradicts those greenhouse-gas warming models that assume that the "heat island" effect is of little or no significance. To the best of my knowledge, that is the majority of them.

Not really. The overall temperature difference is the same. This is just affecting how the change is distributed. It's notable, and explains a known issue with the models, but it doesn't in any way invalidate the overall predictions, i.e., things are getting warmer.

Seriously, the entire waste heat production of humanity is nothing compared to solar heating. Solar heating is ~170 petawatts. The total energy production of humanity isn't even a tenth of a percent of that. Closer to a hundredth of a perce

Here's the thing that should clear on the order of crystal to those most sentient amongst us: if there is the slightest chance that our wanton use of the earth's resources is not without global consequences and repercussions, we are fools if we don't do everything we reasonably can to mitigate the damage our presence creates. We may or may not be the only self-aware species on the planet, but there's a decent probability we are the most self-aware, and one would imagine that incredible privilege comes wit

"Fascinating. Jane's "I don't need a citation" reflex is so deeply ingrained that he doesn't even notice that the citation request was directed at viperidaenz's claim."

It is neither a matter of reflex or "not noticing". It is a matter of how Slashdot shows the comments. Slashdot has changed a number of things about their format lately, and whose comments are in reply to whom is not as obvious as it once was.

The way it is displayed on my screen, it appeared to be a reply made to me. Maybe one of these days I'll find a setting that shows them more clearly.

The heat island effect has always been taken into account for purposes of observation - when some of your data points are located in cities, you need to either discard them or compensate in some manner. This study shows that the effect covers a far wider area than previously thought. A few minor revisions to the models are needed. That doesn't mean previous predictions are suddenly all wrong - just that they are not as accurate as they will be once these revisions are implimented.

One of the concepts that interested me in Larry Niven's classic science-fiction work Ringworld [amazon.com] is a civilization having to move its planet out from its sun in order to avoid perishing in their waste heat. I haven't seen that possibility explored so much in the years since. With studies like this, along with Kurzweil-ish woo-woo of extrapolating growth, can we talk an amusing guess at how long until heat waste renders the Earth, or at least certain parts of it uninhabitable?

The excellent "Do The Math" blog estimates that we have 400 years [ucsd.edu] until we're consuming as much energy as the planet is receiving from the sun. That's a good rule of thumb I think. Anything beyond that and by definition we can't have our current combination of albedo and surface temperature.

Interestingly that estimate also states we have about 1500 years until we're using as much power as the sun produces in total, and we'll need to use the entire galaxy's power output in about 2500 years.

Even if we develop near light travel and start to explore deep space with multi-generational bio-sphere ships we could easily use energy on such a scale.

Lets assume we can accelerate a space craft to.9C, that puts some near by galaxies in reach, within a few generations. I don't think you anything beyond that is practical because I don't think for social reasons it will be possible to stay on mission when none of the oldest living crew people can remember any of the folks who started out.

Why would I mess with something so slow? I have 32Ghz (4Ghz * 8 cores).

As for the bunnies, we don't have quite that many here. We've been burning them to keep the steam engines running.

twenty vw beetles from 1960 don't go as fast as a single ferrari from 2013, no matter how much arm, intel and amd are trying to convince you.besides, we're already making energy that doesn't originate from the sun..

Yeah, esp all that "post scarcity" bullshit.There may be zero scarcity of smurf berries and farmville farms, but despite GM etc there will be an upper bound of wheat and other food that you can produce on this planet. You might be able to survive on food produced via nuclear energy, but given that there are already significant health differences resulting from merely different diets, I doubt humans would thrive on that.

We might be able to postpone things by developing space colonies - the asteroid belts hav

One would think there would be a way to convert the waste heat to let's say microwaves and shoot them at the moon. With a proper array on the moon you could immediately power a lunar civilization and remove earth's waste heat, two birds with one stone. If we created a small device that converted waste heat locally to hydrogen by splitting water, we could reclaim that energy or a reasonable amount of it. Heat concentrators could be used to remove heat from our cities where it would be converted to a frequen

Currently we use tens of terawatts. The power output of the best continuous-fire lasers or maser (and I use that term loosely) is on the hundreds of kilowatts. Pulsed lasers peak in the mega- to terawatt range but average power output is a lot less.

But what percentage of our industrial process ends up being waste heat, and what is the largest feasible array of transmitter one could reasonable build in, let's say the middle of the desert? Clearly the idea of building arrays of thousands or tens of thousands of high powered emitters would be daunting, however for any society looking to move their planet to accommodate increasing waste heat, it would seem to me should have the where with all to create huge, high efficiency quantum emitters to convert was

With studies like this, along with Kurzweil-ish woo-woo of extrapolating growth, can we talk an amusing guess at how long until heat waste renders the Earth, or at least certain parts of it uninhabitable?

Probably not. You've got to remember, that all this carbon we're currently emitting used to be a part of the carbon cycle. The Cretaceous period had half again as much atmospheric carbon as we do currently. A warming world might inconvenience humanity, and probably a bunch of other species, but it will advantage a whole bunch more. For the world as a whole, it's pretty much unimportant - it's been through such changes before.

This is part of the problem with the semi-religious zeal of the lunatic fringe of t

Serious, first thing to look for a thermal is the local town, absent mountains or hills. A large parking lot already does do fine. I know of a military airport which has a cemetary nearby, the dense black marble is sufficient.

The glider pilots in the DFW area refer to the plowed black-earth fields east of Dallas as "Texas brick lifters" in what I have been told is only mild exaggeration. So apparently heat island effects are not relegated to urban areas.

I've seen a map of thunderstorm frequency for UK which shows that a majority occur directly downwind (in prevailing wind direction) from cities, and size and frequency of storms is related to size of the city. Thunderstorm frequency and severity also relate to frequency and severity of lightning damage and hailstorms.
If I can find that again, I'll post a link (unless someone else gets there first).

I wonder how long it will take for someone to research downwind effects of some of the huge wind farms that have been built. Taking that much energy out of the atmosphere should theoretically have an effect that might be measurable.

I don't know about its bearing on models, but there have been studies that umade claims about data selection that could not have been accomplished due to a distinct and complete lack of the information necessary to make that selection, that have ruled that the heat island effect has no meaningful impact on the temperature record (I'm looking at you Wei-Chyung Wang, bullshit science fraudster.)

I love it when when, when converting US customary units to SI units, the precision of numbers suddenly increases by orders of magnitude. 1000 miles is obviously an approximation. Let's be charitable and say it means 10x10^2. If you convert it to kilometers the precision should stay the same. 10x10^2 miles is about 16x10^2 or 1600 km.

You've still got too many significant figures in your output. There's only one in the input, so 2000km.

That's correct, but practically speaking, when you translate some statement about reality you may want to avoid making the statement more surprising than the original statement. In this case you'd be spicing up the story quite a bit if you rounded it up to 2000 km.

Strictly speaking you're right, but as it is not a scientific article I think you're allowed a little leeway in deciding what the actual precision probably was. After all there is no way to tell whether 1000 really means 1x10^3, 10x10^2, 100x10^1 or precisely 1000.

He makes a compelling case, the refutation of which has been on the order of "of course they considered this, they're experts"...when there's no trace of such analysis or correction applied to East Anglia conclusions or IPCC reports through at least 2005 (after which I stopped bothering to read them).

How do those Europeans do it - managing to lower Europe's temperatures with their waste heat? Why can't we do that?

On a more serious note, we all know that man-made stuff affects weather patters, but every large natural thing affects weather patterns as well. The weather is easy to affect, but what we should care about is not whether we affect the weather, but whether we do harm. Too many people run these together.

"Living in dense cities makes for certain efficiencies: being able to walk or take mass transit to work, living in buildings with (at least potentially) efficient HVAC systems, and more."

None of these are valid justifications for cities.

Transportation: I can and do walk, rarely needing a vehicle. No need for mass transport either. I live on a farm and work there as well as in the forest. No need to drive. I often go months without getting in a car or truck.

Efficient HVAC: Our high thermal mass, well insulated home is far more efficient requiring far less energy for heating than city buildings and it requires no cooling. It also doesn't affect the local or distant environments.

Cities stink, are filthy dirty, centers of disease and filled with vermin of both the four legged, six legged and two legged sort. Cities can't produce their own food or fuel and they can't get rid of their own wastes. Studies show that they are black holes, blemishes on the environment, soaking up the resources and polluting thousands of square miles around them.

This crap again? Astronomy fits that narrow "not a science" description as well. I dare you to walk up to Buzz Aldrin and tell him astronomy is not a science. This "debate" is on the same level as the moon landing deniers.Anyway, from what I've heard there are this things called digital computers (that thing you are using to convey your silly luddite drivel) that can model the theories of the climate scientists, and then the models can be compared with reality. This gives you those five steps.

Something doesn't have to be scientific to be truth. Philosophy, history, mathematics - all have means of determining "truth" without relying on the scientific method. The problem is that "science" is increasingly taken to mean "rational", when that is not true - science is a subset of rationality. Stating something is not scientific is not necessarily an attack against it; it's purely descriptive.

First, what you do not seem to realize is that astronomers DO conduct experiments. They gather data, crunch it down, and see if the results compare with their hypotheses.

Second, there have in fact been a very large number of detailed physical experiments in astronomy. Apollo 8 was one such: no one knew for certain that the figure-8 "free return" trajectory family would really work, until they tried it in real life with a real spacecraft.

As for your comment about digital computers modeling the theories of the climate scientists, THAT EXPERIMENT HAS BEEN TRIED. REPEATEDLY. Every single climate model out there, when started with available historical data and allowed to run, FAILS to predict today's climate. A model which provably does not match reality is, by definition, an invalid model, no matter how cheap or how fancy a computer you ran it on.

So where does that leave mathematics, the applied sciences and who are you anyway to tell us that the dictionary is wrong?

CAN find opportunities where the universe has set up experiments FOR US

So what's so special about climate science that they are unable to exploit those opportunities? Where are you drawing the line tmosley? Geophysics? Geology? Microbiology? Come on now, it's your own private definition so let us know what it is if we are all supposed to be wrong if we don't stick to it. Define it

When questioned with PR company lies that answer is a fairly obvious response.When one "side" pretends that if the other is not omniscient then everything they say can be rejected and replaced with a handy PR lie that's when you get assertions of certainty in response. Certainty is possible in general terms even if unreasonable levels of precision is not.

Where's your rigorous testing for that assertion?

There is a website called "google scholar" now so there is no longer any reason to pretend there is no rigorous testing just because you can't be bothered to ever set foot in a library before making these wild claims. What is this bullshit about flooding the net with noise to try to shout down anyone with a clue? Do you realise that your anti-expert bullshit is having fallout in other fields, and if you are good at anything at all such a line is going to backfire on yourself if it catches on?

Asserting climate is the average of weather over the long term, again sounds wooly and not a high standard

I think it's about time to graduate from the childrens dictionary Bongo if you are attempting to be credible.

Climate is by definition the average large-scale atmospheric conditions over the long term! You can't complain about that, any more than you can complain that temperature is a measure of the distribution of kinetic energies of an ensemble of particles.

Your unstated premise that the models are over-fitted and poorly checked against data is simply not true.

Isn't this comment more or less an archetypal example? Veiled and nonspecific allusions to error, uncertainty, and weakness? No actual substance? Nonspecific accusations that could be leveled at any piece of research? Let's look at the issues you raise.

"The question is always, how do they know? What did they do to arrive at that result?"

It's in the papers. And countless popular accounts.

"...does not sound like a high standard."

That's why your rhetorical scenario is not the standard to which climate science is held. If you're interested it's... in the papers, and in the countless popular accounts.

"Where's your rigorous testing for that assertion?"

It's in the papers, and countless popular accounts. Assuming, of couse, you do not set an arbitrarily strict limit for "rigorous" that excludes them.

Isn't this comment more or less an archetypal example? Veiled and nonspecific allusions to error, uncertainty, and weakness?

When the comment is about the veiled and nonspecific "scientific process" of climate science, then no.. its not an archetypal example.

Science is a process. Are climate scientists following the process all the way through? The answer is that no, they are not, and certainly they cannot be blamed for not doing so because they dont have an atmosphere to perform tests upon.

But the lack of blame in no way elevates the process that they do accomplish to a level above what it actually is. The parts of the scie

Consider a simple physical experiment. A ball is suspended 16 ft (4.9 m) above the ground. It is released at time t=0 s. We know from countless high school science demonstations and countless college freshman physics labs that the ball will impact the ground at about time t=1 s, and it will be moving at about 32 ft/sec (9.8 m/sec) when it hits. Using a stroboscope and a camera, we can determine its position with reasonable accuracy and precision at, say, 0.1 s intervals.

i am sorry sir, though you have all the symptoms of cancer i can't really prove scientifically that you definitely have it. So i can justify giving you this expensive treatment. Come back in 20 years and we'll see if its got any worse.

and you'd be surprised about per capita pollution compared to just 50 years ago and even more surprised to 100 years ago when things were a real mess in most big cities still(pumping sewage straight out, burning shitloads of coal within city limits etc..).